import 'package:flutter/gestures.dart';
import 'package:flutter/material.dart';

class BottomSheetScrollEvent extends StatefulWidget {
  const BottomSheetScrollEvent({Key key}) : super(key: key);

  @override
  _BottomSheetScrollEventState createState() => _BottomSheetScrollEventState();
}

class _BottomSheetScrollEventState extends State<BottomSheetScrollEvent> {
  ScrollController _scrollController = ScrollController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("底部弹窗和listview手势冲突"),
      ),
      body: _buildBody(),
    );
  }

  Widget _buildBody() {
    bool isOutScroll = false;
    return customGestureDetector(
      onDown: (event) {
        print("onDown");
      },
      onUpdate: (event) {
        print("onUpdata event.delta.dy：${event.delta.dy}");
        if (isOutScroll) {
          _scrollController.position.pointerScroll(-event.delta.dy);
        }
      },
      child: ListView(
        controller: _scrollController,
        children: [
          GestureDetector(
            onTapUp: (event) {
              showBottomSheet(
                  context: context,
                  builder: (context) {
                    return Container(
                      height: 100,
                      color: Colors.white,
                    );
                  });
            },
            child: Container(
              color: Colors.orangeAccent,
              height: 100,
            ),
          ),
          Container(
            color: Colors.blue,
            height: 100,
          ),
          Container(
            color: Colors.green,
            height: 100,
          ),
          Container(
            color: Colors.red,
            height: 100,
          ),
          NotificationListener(
            onNotification: (ScrollNotification notification) {
              if (notification is OverscrollNotification &&
                  notification.metrics.axis == Axis.vertical) {
                isOutScroll = true;
                print("$isOutScroll");
              } else {
                isOutScroll = false;
              }
              print(notification);
              return false;
            },
            child: Container(
              height: 200,
              child: ListView(
                // physics: ClampingScrollPhysics(),
                shrinkWrap: true,
                children: [
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: Container(
                      color: Colors.green,
                      height: 80,
                    ),
                  ),
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: Container(
                      color: Colors.orangeAccent,
                      height: 80,
                    ),
                  ),
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: Container(
                      color: Colors.greenAccent,
                      height: 80,
                    ),
                  ),
                ],
              ),
            ),
          ),
          Container(
            color: Colors.green,
            height: 100,
          ),
          Container(
            color: Colors.blue,
            height: 0100,
          ),
          Container(
            color: Colors.yellow,
            height: 0100,
          ),
          Container(
            color: Colors.grey,
            height: 0100,
          ),
        ],
      ),
    );
  }

  RawGestureDetector customGestureDetector({
    GestureDragDownCallback onDown,
    GestureDragUpdateCallback onUpdate,
    Widget child,
  }) {
    return RawGestureDetector(
      child: child,
      gestures: {
        _MyVerticalDragGestureRecognizer: GestureRecognizerFactoryWithHandlers<
            _MyVerticalDragGestureRecognizer>(
          () => _MyVerticalDragGestureRecognizer(),
          (detector) {
            detector
              ..onUpdate = onUpdate
              ..onDown = onDown;
          },
        )
      },
    );
  }
}

class _MyVerticalDragGestureRecognizer extends VerticalDragGestureRecognizer {
  @override
  void rejectGesture(int pointer) {
    print("----->rejectGesture");
    acceptGesture(pointer);
  }
}